Yeah we do. Up to your personal preferences. Some people do not fancy the extra weight just for that few extra shots. If you can forgo the shots that needs tripods, or do not mind ISO 1600 and above, you can skip the tripod.
Search the forum, many threads regarding travel+tripod and flight+tripod.
For sure...without a doubt my best and heaviest tripod will follow. Even if it is my usually trip to Malaysia to visit relatives, mytripod is always there with rest of my gear. For trips that are like what I call "trip of a life time"..you definitely should have it along with you. How often do you make that kind of trip?
If night photography is not your cup of tea then sure...leave it at home but at the very least you still would need a monopod for those slower day shorts in the shade or you have to shoot it under slower shutter speed.
IfF you are passionate about photography and the trip is an important one...really man...this question should not even pop up...the tripod is a must.
Carrying your tripod around? Well I would work out to train myself to carry that extra weight. CArrying weighty gear I guess for me personally is no biggie even at my age since I started off shooting SLRs way back then. And most lens and bodies back then were heavier but I have never once regretted it...even if I come home with a sore back. Sore back will heal. (even made me stronger over time) Your next trip to that country might be months or years or never to come again. Why chance it?
can consider getting the slik sprint pro tripod, its light weight and can support pretty heavy gear for its size what i like is it is 4 section with 3 joints, hence it folds down to a small size and you can bring it into the cabin or keep within your check-in luggage within clothes easily even if it is a small hand luggage.
As mentioned, if u are going on holiday with gf/wife/family, consider whether you are likely to use it. Usually in such cases, you have little time to use tripod. Also, if u think of using the tripod and mount ur slr to take picture of yourselves and gf/wife etc, think again as it may be robbed. bring a small pns camera and ask the "most friendly, honest looking fellow to take for you "
On a side note, for those interested in a ultra small tripod for travel, velbon just came out with one that looks interesting. It's call ultra mini or something. Worth checking out.