The word degust means "To taste something carefully, so as to appreciate it fully", according to the Oxford Dictionaries website.
So, it does not sound like degusting one's meals should be considered a 'bad habit' or 'rude' or otherwise inconsiderate of others who might not practice it, but I'm guessing it could be a source for some tension or friction or impatience at times.
For example, if I prefer to degust every bit of my meal, it could lead to a lengthy and potentially selfishly-isolated experience. If I am in the company of others, degusting every bite could be considered very rude indeed, especially if I was prone to making facial expressions or sounds to accompany my degusting actions!
It becomes prudent, then, I think, to refrain from practicing too much degusting when in the company of others. After all, OVER-tasting foods might actually have negative consequences even with regard to how one feels about some foods or drinks.
Sometimes, it might be better to just "skip the degusting, and just gobble it all right down", y'know?