In a word, yes.
Blasting is abrasive, so, it removes metal. It also tends to harden the remaining metal. Both of those actions can effect the spring rate and integrity of the bar.
Now, that’s the theory. In practice, if you don’t blast the everloving crap out of the bars, you probably won’t notice a difference. And the longevity of the bars shouldn’t be dramatically reduced. Doesn’t mean you haven’t effected the bars, just that the difference is likely to be pretty small unless you really get carried away. Still not the recommended way to do it.