I have a potential problem coming up. Beginnings of next month, I'm travelling down south. When I arrive I won't be able to check into my hotel straight away as I have to go straight to a bar for a gig. I'll have a big suitcase with me, which will have shaving foam and paper plates as I'm planning a session after said gig.
My problem is if there's security staff at the bar and they ask to check my suitcase, how would I get round explaining the amount of foam if questioned about it?
Am I worrying about nothing or should I prepare for an awkward conversation about it?
What do you think?

Where you coming in the south? Lave it with me, I cant promise the contents won't be used:p

London first, then to Brighton.

"I'm going to have a pie fight with it after the show. "

Seriously. More often than not you'll get a "can I join!?"

Depending on where your various things are, you could use left luggage at the train station? Not sure if they check (I've only used it abroad!)

The left luggage at King's Cross uses a scanner, so might be a risk.

It's fine. I'll just own it if they ask

Check with your hotel- the need to store luggage is a fairly common problem so a lot of hotels offer a bag store for their customers.

If my train gets in early, I will gladly do that but I don't think time will be on my side. I'll just roll with it

If the idea of using the official left luggage at King's Cross is concerning, there are apps (Bounce, Stasher, LuggageHero, probably others) which will let you store bags in back rooms of local newsagents (etc.) at rates that are probably less than those of the official left luggage, within 3-4 minutes' walk of the station. I've used one once - can't remeber which one - and had no issues but that's hardly a convincing sample size and it did feel the tiniest bit sketchy even despite convincing guarantees. That said, they don't have a bad reputation, so I wouldn't have too much hesitation in using them again. Do you own research, check suitcase size limits, opening times and so on.

I must admit, I've used that service once and, as you say, it felt a bit odd - but was otherwise fine...

I love using Bounce when I travel; whilst not used for a session, I have left cases at convenience stores in many countries and have had a great experience in them all. It is cheap and there are literally dozens of locations in large cities like London. Can't recommend enough.