Maybe the locals can make some real money without having to deal with cheapskate trekkers bargaining down the price of a room from $5 to $4 while they stand there in their $200 shoes.
Cheapskate trekkers do not help enough financially.
One must be careful. Paying higher prices may or may not be a good thing. As I understand it (correct me if wrong), there is a reason why lodging and food prices in the Annapurna area were more or less fixed by the government some years ago (not sure if they still are).
I do know that in the past (especially the 1970’s and early 1980’s) that there were some areas in the Himalaya that experienced “hording problems”. If an expedition or a season of trekkers came through and was willing to pay (or trade) much more than the locals, then few would trade/sell with their neighbors/other villages. If you could sell your neighbor an egg for $0.10 and some foreigners came through and were willing to pay $1 for one egg, then whom are <i>you</i> going to sell to? Having foreigners pay much more may or not always be a good thing and I understand that this was the primary motivation behind the prices being more or less fixed. The Sherpa (and many other ethnic groups) economy has been more heavily reliant on trade rather than agriculture.
Although cheap by western standards, foreigners still do pay higher prices than locals for goods and services (for example the price a porter pays for a meal is (or was) also fixed. Over all, from a monetary standpoint, trekking has been positive for Nepal and the regions where trekkers visit. Most of the locals want the trekkers there and try to attract them and are warm and welcoming towards them.
As far as being cheapskates, it seems like most of the clean water and electricity (among others) projects in Nepal have come from aid from Europe, Japan, China and the United States among others. Just a quick search shows how much foreign aid goes to Nepal:
http://en.wikipedia.org/wiki/Foreign_aid_to_Nepal