if I buy a restaurant and become the owner could I show  up at any time and demand I be served first and not have to wait?

Yes.  Why wouldn't you?  You need to be able to have a "no notice" type inspection.

I would guess that if you wanted to have customers keep coming in that you wouldn’t cut in front of them. If you were the owner and I knew it and you did that to me, you would lose my business and probably that of others

Silly, sentimental me - when I see restaurants go out of business, I am saddened and think, "There goes somebody's life savings, there goes somebody's dream." It's really bad with the Covid situation - a few are making it big with delivery, mostly chains and franchises, while the rest try desperately to hang on. 

It never, ever occurred to me that the entrepreneurial restauranteur's dream was to be able to "show up at any time and demand to be served first and not have to wait and fire the workers who would not comply." 

Maybe you have a blood sugar problem?

you can but i hope you dont do it

Yes but jerks may have trouble keeping good employees.

It seems likely since you probably won't have a lot of customers these days, but it would be puzzling to anyone with the slightest bit of logic as to why you throw your money away on what has become the worst investment in modern times instead of just hiring a private cook to come over and make you any meal you want, whenever you want.

You 'could' do this, but don't be surprised when your paying customers get upset and choose to go elsewhere.

What a stupid as$ lame question.

Sure.  You might lose a few customers though if they saw you do that.

Not if you're smart.  The customers who were waiting (and would have to wait longer) would be pissed.  The restaurant would lose business.  You would lose money.