Travel and the increase in travel does add environmental pressures. One must get somewhere one way or another (and increased travel means more train or plane passengers). You're also buying things to adapt to the destination's weather, etc. It all adds up.

Also, at the destination, more people puts pressure on the ecology there. Imagine everyone being able to afford going to Antarctica, or let's say, the Grand Canyon or Mt Fuji. It's be environmentally disastrous. We'd eventually have to regulate access as is currently done for places like Antelope canyon.