Can I bartend in USA or Canada without the required visa?

Okay, so, here's the situation. I want to live and work in the USA or Canada, as a bartender, or maybe as an English teacher. Problem is, as I understand it, it's more or less not possible to get a working visa for either country.

The USA apparently doesn't really give any visas to people unless they are highly skilled or getting married to a US citizen. Canada apparently has an age limit of 30. I'm 32, male, British.

I'm prepared to fly out to either country and risk finding work without the required visa. What I'd like to know is:

As a bartender, how difficult exactly will it be for me to find work without having to prove I have the required visa? Would a bar manager demand to see it?

Will I have any problems finding accommodation wothout the required visa?

How likely is it really that I will be caught working illegally?

I'm sure many people do this in both countries, is it realistic to get away with?

Has anyone reading this done it themselves or knows anyone who has?

Please let's skip the potential moral argument here, I have my reasons for needing to do this and I'm just looking for clear answers to my questions, rather than a debate about playing by the precise rules.

Thanks in advance