In all fairness, Europeans have to travel to another country for a change of scenery or vacation. Here in States all people have to do is go to another State to accomplish the same thing. Heck, I travel further to go from one end of LA to Orange County than some Europeans go to visit another country. And trust me, there is a whole culture shift going from East LA to OC.
Its honestly pretty interesting to me just seeing how different rural CA is from urban.. Im not talking scenery.. Im talking culturally.. and how different northern CA is from Southern CA..
drive a few hundred miles and get across the NV border.. and you have yet another completely different world..
people talk differently.. have different priorities and values.. the terrain is completely different.. etc..
In California and the adjacent states alone you could spend a month traveling and still not take everything in..
Texas is similar (although a lot less interesting I think for people as tourists).. the hill country is a completely different world than North Texas... East Texans are very different people than West Texans.. the way they dress, the way they talk.. the things that are important to them, etc.. is very different.. and the border area is completely different than the rest of the state..
The diversity in our larger states in terms of their people, their food, the weather, the terrain, etc.. is every bit as complex as varied as parts of Europe... and when we start talking about Americans from different parts of the country (Boston vs San Diego.. or Houston vs Chicago.. or New Orleans vs Seattle, etc)... Id say the complexities and variations exceed many neighboring countries in Europe..
People forget.. Belgium is a little less than 12000 square miles.. Portugal is a little less than 36000 square miles.. Switzerland is about 16,000 square miles...
California is 164,000 square miles.. and Texas is 270,000 square miles (two very densly populated states)...
As a rule we don't have to leave the country to see and experience different things.. often times we don't even need to leave our own home state...
You can drill down even further and look at our major metropolitan areas.. google any obscure type of food you might want to try.. or any sort of cultural festival you might want to attend.. moroccan? ethiopian? peruvian? czech? bosnian? russian? mongolian? vietnamese? korean? You will find quite literally dozens of options for any of them somewhere like Dallas, Chicago, or Los Angeles.. as all of our major cities are melting pots of foreign cultures and people (we have almost 50,000 ethiopians in Dallas.. 200K indians in the DFW metroplex.. Dallas has the largest Czech population in the US.. We've got 12,000 bosnians, a couple of thousand peruvians.. etc..etc..)..
Yesterday I gave blood.. my phlebotomist was a nigerian.. we had a fun time talking about Abuja, how cool the city is.. how Muslims and Christians get along really well there (when you take the highway going through the center of the city there is a huge mosque on the right hand side, and a huge Christian church on the left hand side.. within just a few blocks of each other.. and everyone gets along, etc..etc.. I told her that the best Chinese restaurant Ive ever eaten at in my life was in the Sheraton in Abuja.. she knew the restaurant well..
Its not real hard to get exposed to foreign culture, foreign people, etc in the US if any attempt is made at all.. and you never have to even leave your home state..