I drive my 5 speed all the time taking off in 2nd. If I am starting off up a significant hill or I am pulling a decent load, then I will use 1st. Otherwise on flat ground I just take off in 2nd even with my boat (2,000 lb) behind me. But at the boat ramp, I use 1st all the way up and just basically idle up out of the water.
1 st gear is somewhere around a 6 to 1 ratio with 2nd being somewhere around 3 to 1. Most automatics run somwhere around a 2. 8 or 2. 6 to 1 ratio for their 1st gear. Really there is no more clutch slippage taking off in 2nd on our trucks as compared to the amount of slippage it takes for a gasser car or truck to take off in their 1st ratios.