Well, you can get some of the nerkmids cheaper. For instance, I decided to buy one for the avatar, and got the Basic Golden Nerkmid for about 82,000NP. You can find the basics for 80-90,000. Quite a few are more, but you should be able to find one at that price.
Now, the Average Nerkmids are more valuable. 105,000-120,000. Essentially, your odds of getting junk gross food are very high. Sure, you might get a paintbrush, and I hope you do. Just don't count on it.
What I'd consider doing is selling the Average Nerkmid, buying a cheaper one like the Basic, and pocketing the difference. Of course, they say the better the nerkmid the better the prize, so you'll have a bit better chance of a good prize with your average nerkmid. You'll have to decide whether to take the sure thing (profit from sale) or take a chance with the better nerkmid. Either way, if you decide to use a nerkmid in the machine, you'll at least get the avatar!