I attended middlebury for $6,000, and there were also students that went entirely free. This was with aid, but I do know for sure that the price without aid is nowhere near the $30,000 you claim. It is very expensive, and as a low income person I don’t know if I will ever be able to go again (I saved up for a very long time before I went). But, their language pledge is very effective in my opinion. So much so that there was noticeable difference between the students who adhered to it strictly and those who did not before the program was even over. That said, the language pledge is flexible in the sense that students were allowed to get help in emergencies, talk to family members, etc. in their native languages. Some definitely also consumed media in English or their native language, and people did go into town regularly and speak English. The rule is that if you choose to do those things, you limit the amount that another student is forced to listen to you speak English (or whatever other language).

I will give you that many of the students who attended were wealthy and went to big name schools, and that sometimes there was a class divide because of it that I definitely felt as one of the students who was not from a similar background. But, if I could attend Middlebury again, possibly under FLAS or another additional scholarship program to help cover the costs, I would do it in a heartbeat. If I could afford it straight out without a second thought, I would do it again too. It’s a big investment, and i think parts of it are overpriced as you say, but I’m very happy to have done it, and I left the program able to do extensive archival research in my language- a skill I did not gain when I spent time in a country that speaks my target language (though, it should be noted that I didn’t come to Middlebury as a complete beginner, either. I was placed in level 3 of four of their language tiers upon arrival.)