I went by a faucet shop to see what kind of garden faucets are
available. I was surprised when the salesman showed me a couple with
hot- and cold-water connections.

I thought, who waters their lawn with hot water? But the guy made a
decent point that if you want to wash your deck or something similar,
it may be good to have warm water.

OK, good point, and I might go for it, but still I can't remember ever
seeing a garden faucet with hot water connection. Have you seen it, or
even better, does your garden have such a connection? If so, do you
find it useful in practice?