I think people need to see the bigger picture. They see a model priced at 125 dollars or even 100 dollars and say damn that's too expensive. I've looked on here and a typical high quality vehicle model is between 99 - 119 dollars. Which is very good price considering a vehicle model done accurately can take weeks to be made. No one becomes rich from selling 3D models online so do you think artist make a fair amount on their assets? If the person sells 1 model per week or per month, do you feel 125 dollars is too much to ask for a few weeks of hard work?
Sellers who under cut are a problem, but only barely as every buyer especially high profile buyers are smart enough to know that low priced models means low quality work the majority of the time. I've found people are more willing to pay more ensuring the quality rather than risk paying less for something that will more than likely be dodgy.
Think of yourself as a working person. You won't go work at a job for 100 - 125 dollars per week or per month will you? So why do people expect artists to sell for lower? let alone that amount. You might say that through their work they may get offered higher paying jobs, or they might make money through the quantity of models they sell. But this only lasts so long, each model made has to appeal to a good number of buyers. The artist has to continually produce more and more regardless if they are getting any job requests that pay higher (which many don't). People who think models are priced too high need to step back and have a re-think on what the artist goes through to develop such assets and provide them for such a price. In reality, the models are worth far more than what they are priced.