I'm about halfway through watching Stargate SG-1 and I noticed several occasions where SG-1 fought Jaffa forces near the stargate. While they often had to leave in a hurry, there were many situations where they would have had the time to take some of the defeated Jaffa's weapons with them back through the gate.
From what I've seen so far, the SGC only has a handful of zats and Teal'c's staff weapon, but it seems to me like they could easily have brought back dozens of staff weapons and zats by now, which would certainly have been useful for research or simply as an addition to the arsenal.
Is there any in-universe reason why they did not salvage more weapons when they had the chance, or is there something wrong with my assumptions?