If the induction seal is complete I like it because it, more or less, means no leaks, period. And, since there have been a number of threads in this forum about wanting to make sure you are getting exactly what the label says the foil is another layer of protection against tampering.
I'm not talking about cyanide in Tylenol. One could throw some powdered citric acid into the oil, or even some very fine sand. I wouldn't put anything past people these days.