I use almost exclusively cash and never get that response. Usually a smile as I sail out of the cashiers way faster than our abrtion of a chip+pin system customers possibly could. What part of the world are you in?
Pay with cash at a bar now and everyone will sigh as the barman counts it up, puts it in the till etc etc. Contactless is so fast, the barman will be pouring the next drinks while you're tapping the machine.
Also anecdotally, many London cafes/restaurants are entirely card payments now. They just don't do cash.
The legal tender laws just mean that if you offer a sufficient quantity of legal tender in settlement of debt, your debt is discharged and they can't sue you for non-payment. This ensures cash has value, and means that most shops will take most forms of cash, even if it means queueing up for counter service because the kiosks are card only
For instance, if you are at the bar and they pour you 3 drinks then ask for payment, they have to take your cash.
On the other hand if you are at the bar and, ask for a drink, and they say that'll be $10, they are not required to take your cash (the debt has yet to be incurred) and are also of course not required to provide you that drink if you pull out a $10 bill.
It is more or less instant. Common in .au, .nz at least.
I'm actually noticing some cultural changes as a result of this, cash is starting to seem "dirty" since you often have to touch other people's hands to exchange it.
Only last year I always carried cash. I like cash. Now, I have a $10 note in my wallet and I can't even remember where it came from. I've stopped actually carrying my wallet, thanks to Apple Pay on my watch.
(I live in a major metropolitan area. It might be different elsewhere.)
I just spent a few months in the US and didn't use cash once (LA, SF, NYC).
I went to many places that no longer accepted cash in the US, maybe we're just in different areas.