That's kind of the problem though, if you are trying to learn and people just switch to English it's difficult to make progress.

I've had situations in France where I ended up having one side of the conversation in French and one in English!

It's a tricky situation as a language learner. On the one hand, you've got to be polite, trying to converse with people in their native language, on the other, you don't want to waste their time just for your own language learning goals.

I live in Germany and I always start conversations in German, but if it becomes clear that their English is much better than my German, I switch to English to spare them of the burden. It's not the barista's job to indulge me in my learning pursuits :)

Getting out of the big cities tends to help. Or even just out of the tourist area. The last time I went to Nice, for example, I found it hilarious that within Carre d'Or, people would switch to English when I showed the slightest hesitation with my French, or the first time I made an error (so, quickly). But just a few steps into Liberation, minutes walk away, we kept coming across shop staff that kept speaking French no matter what horrible crimes I committed against their language...

> one side of the conversation in French and one in English!

This is actually an effective way for two people to practise each others' language, and is adjustable according to aptitudes:

Easy mode: each person speaks their own L1

Hard mode: each person speaks the other's L1