More dirty tricks in Ju Jitsu compared to other martial arts?

Rules are part of the sport aspect of martial arts. These are generally safety related for competition, although there may be other origins as well. Many of these rules make no sense in a real fighting situation. For example:

1. Judo - you can't hit people
2. Tae kwon do - you can't throw people
3. Boxing - you can't hit people from behind, kick people, or push on the hands

From the point of view of any of these sports, the other sports are dirty. Also in the context of these rules, a real fight will be dirty because there may be punching, kicking, grabbing, and certainly no one is going to stop if they get behind you or the fight goes to the ground.

Consider, however, that just because a technique is "dirty", it does not mean the technique is also effective against uncooperative partners, or that you are sufficiently trained for it to be so.

When judo was founded, Jigaro Kano put a lot of thought into what techniques he thought were effective versus what could be trained without injuring people. At the time, many of the jujitsu schools held the opinion that "our techniques are too dangerous to be practiced on people" -- they were dirty. In the 1880's there was a competition between the dominant jujitsu schools of the time and judo. Judo won handily because its students trained randori (free practice, not prearranged). I am not trying to say anything about judo and jujitsu today; the point is that techniques that were well practiced won against techniques that were not as well practiced.

I don't have the context for trying to put fingers up someone else's nose, but this seems like a gimmick. The nose holes are small and if the other person is moving, this seems like an attack with low success rate. I would think it would be easier to put your fingers in their eyes, bash their nose, or grab their ears. But that is not the important point.

In summary, yes, jujitsu has historically had more dirty techniques because it is not a sport or designed for free practice. But beware of the effectiveness of dirty techniques that you can't verify against resisting opponents.