A few points (speaking based on UK law, no idea how it translates to US law):
You can only be prosecuted for trespass if you refuse to leave the property or return after being asked to leave. Being caught is not grounds for arrest. Most people get done for Breaking & Entering
Businesses can refuse any business that they want: they're not offering a 'contract' to sell to you, you're offering a 'contract' to buy from them. They can literally turn down your business with no reason whatsoever.
And if the front door of a business with publically declared opening hours is open, that does not mean an open invitation to the public. Plus you wouldn't get past the lobby/reception usually even if you did walk in.
Posts pics though if you do go
man UK laws are fffuuuucccckkkkeeedddd
enjoy having zero means to defend yourself while i concealed carry
also, shariah law
you guys need to take your country back
OP: gogogogogogoo take video with sound, or atleast pictures
learn as much as possible
OP: Well done, the report doesn't fill me with confidence but good to hear something!