Could Mysterious Cosmic Light Flashes Be Powering Alien Spacecraft?

[defacto7]

5. Theoretically point your radio in the oposite direction

What gets me about even entertaining such travel is the junk factor. Say a million ton craft is bopping along at a couple hundred thousand mph, the liklihood of hitting uknown space debris is pretty miniscule but getting anywhere is also pretty miniscule. Push that up to 10% light speed and you may reach a few places but the probability of running into debris goes up to rather concerning levels. But then if you're powering with FRB's I suppose you could figure out that problem.
Just to say, I think looking into sources unknown is great, tagging it to interstellar space travel seems a waste of time to me.