Earliest closing I know is Bilston Quicksilver, 3pm Sunday. Might be later now.
It sounds like the sort of claptrap that the humourless granny attendent may try in order to 'diplomatically' get you to leave.
I know EXACTLY the bone idle prejudiced staff member you are dealing with there.
Basically
1) The arcade is a clique hole for various harmless doddery fucks to come and dribble over the 10p Party Times and spend all day drinking low quality tea and moaning about the doctor hasn't put any zopiclone on their prescription, all for a £2 spend for the day. This is perfectly acceptable and obviously a cornerstone of any successful business.
2) As the staff won't have been given any formal training, they will have to rely on their wit to detect 'scammers'.
3) A 'scammer' is anyone under the age of 50 who walks in and is not dribbling. Don't think that because you're in your late 30s, with a bit of a gut and some grey hairs and glasses and pictures of your kids on your phone that you're off the hook. Nope you need to be 100% dribbly and doddery to get some humility and biscuits.
4) This post isn't ageist by the way, it's just highlighting the sort of individual who IS allowed to freely congregate in these places. Some old people are great! Just redressing the balance there, I don't want the EDL (elderly defence league) protesting against me.
5) Should you be 'lucky' enough to be left alone, by left alone I mean constantly stared at in the most hostile manner imaginable by the old witch then REMEMBER THIS GOLDEN RULE THAT I AM ABOUT TO TELL YOU....
6) Do not under any circumstances gamble for big money. Don't start sessioning Pure Pots on £2 spins. DO NOT DO IT! Anyone with more than £20 in their wallet who hasn't popped in every day for the last 20 years WILL be UP TO SOMETHING! Also it is the law that after putting £2000 in for £500 you will be asked a fuckwittish question such as "DO you win on these every time then?" closely followed by "You're not from around here are you?" or that old chestnut....
Hold on, this one needs a number of it's own, it's going to be number 7, but I'll count it in as it's used in shitty clique holes up and down the country...here we go...a one.....a two......a one two three four....
7) "IIIIIIII HAVEN'T SEEN you IN HERE BEFORE!!!!!!!!!!!!!!!!!!!!!"

Listen chap, if by now you don't feel thoroughly intimidated for spending £2000 to win £500 you are a honey badger and that's ok as David Attenborough will be standing next to the £5 Golden Games, with no working bulbs in, taking pictures of your hair. I mean it's a cloody cheek. For one, the lovely old witch now has to fill in some paperwork. I mean it's like getting your name and then asking you to sign then she has to sign and file it in the office. You've got a fucking cheek pal, move along now. Then if it's not hand pay as the float is only £48 (an average acceptable float for any B3 in a shithole) she'll have to refill it. THE FUCKING HARDSHIP! Her job description is only making piss poor tea and intimidating you! Naughty you creating all this EXTRA WORK! HOW VERY DARE YOU! GET OUT NOW!
9) Don't attempt facile small talk with a smile. Even the most hearty "It's a little bit cold outside isn't it?" accompanied by a cheery chuckle will be met with a FUCKING IGNORANT BLANK OF BLANKS and a COLD ICY STARE.
10) Don't park on double yellows or even double park as you're obviously about to rob the place and THE POLICE ARE ON THEIR WAY WE ARE NOW CLOSED! And how can you even afford to drive a car? You must be a criminal. I've been embittered all my life and I've got this mobility scooter to show for it. Jog on fellow.
11) Lastly, remember it's not a museum. You can't muse over the various machiens and choose which one to play at leisure. Oh no as you are magnetising them all with your eyes, so they pay out later. No. Quick. Choose. Now.
I WILL FOLLOW YOU AROUND STANDING ABOUT 3CM BEHIND YOUR HEELS. DO NOT BUMP INTO ME OR MAKE EYE CONTACT WITH ME AS IT WILL BE A SOUL DESTROYING EXPERIENCE FOR YOU. DON'T CHECK THE POTS ON THAT POTS OF GOLD.
12) All wins over £3 must be verified by a staff member. All wins over £10 must be verified by a policeman.
13) Oh for the pubs and the heat of the landlord. Oh to hanker after the implied violence, the bitter depressed mopey snipiness of the locals who insist they are just speaking their mind (Only joking O) oh to hanker after THAT sort of heat. The old witch wins again. Psychological games. Expertly played. I wonder how toolers fare in such establishments.
14) Where was it ming if I may be so pertinent as to ask?
15) Chances are I've been there.
16) Unless it's in Scotland
17) Or some of the places up North.