I visit them quite a bit, when I feel homesick and want a taste of the US. My wife does the same when we are in the US, visiting Peruvian places, although granted those are not typically 'chains'.
Of course a person in TGI Fridays would have otherwise gone to a local restaurant, and that 'hurts' a local restaurant, but that's competition. It's a free market economy, and economists generally agree that international free trade is net positive for all parties involved.
But in any case a lot of those chains are franchised and so can be (but may not be, I don't know) part-owned by Peruvians. Not to mention staffed by Peruvians and receiving Peruvian meat and produce for their dishes. So even if you go to McDonalds it's not like all is going to the US and none goes to Peru.