Can't agree more.
Some shows, ST:TNG as a prime example, just about everything possible can be bought, from mugs, clocks, cards to uniforms and models. For SG-1, we get cards and VHS/DVD...
There ARE a few things available, jackets and patches and the odd mug etc., plus a few of Allans products which ARE fully licensed. See some of the other threads in this category for more details.