system
Given the following post, respond as if you're commenting on Reddit:
human
[Harry Potter] Olivander is one of the world's foremost experts on wand lore, so why is he just a glorified shoe salesman?

There are two main times we see him in the books. In the beginning, he runs his wand shop and has a shop filled with little shoe boxes but with wands and scurries around helping people try wands on until they find one that fits. The next time we see him, he's been kidnapped by one of the most powerful and knowledgeable wizards in England to do the wizard equivalent of building him a WMD, because only he has the knowledge to do so. Why isn't this guy a tenured professor somewhere?
gpt
It is wrong to think of him as a salesman primarily.  He is an artisan or craftsman.  He possibly makes the finest wands in the world.  He looks like a shoe salesman because one of the few times we see him is literly the busiest time of year for him.  For one week or maybe even just a day all of the new Hogwarts students come to see him so he is having to work costumer service all day.  Throughout, the rest of the year he is going to be facing no where near that many customers.  

For the rest of the year he is going to be crafting wands experimenting with techniques and materials and generally just perfecting his craft.  True he will have the occasional customer needing a new wand or repair but it will be sporadic.  Basically, the brief period each year of being salesman for new students pays for the rest of year doing research and experimentation.