Of course they aren't. Parlays paying the right odds are a dangerous weapon in a bettor's arsenal. I used to bet dozens of two picks a day.
Anytime you can decrease your risk and increase your reward it's a good idea. Over time the results won't be too bad and in line with your expectation. The bigger the parlay, the more losses between big wins, just volatility.
Unfortunately, the bigger the parlay, the higher the chance that the bettor is getting shorted on his payout.
You should be getting +265 for at two pick, but +260 is acceptable when you have no choice.