Why don't we grow trees like Pipal,Neem,Bargad,Nilgiri now a days on roadside & nearer to colonies we reside?

If you reside in a country where these trees are native, you should grow them because they will take less water and tolerate the climate better than imports. Reputable plant nurseries will tell you what is native and what is not but will grow successfully in your area. Go native, if possible, and enjoy what nature has provided.