this is just as likely true as not true.
enterprise sales organizations often do research on individual companies or market verticals, add entries into a big list, maybe combined with other marketing/sales people, and then do a mail merge from their CMS or other software.
just because the sender may not have realized this particular corporation was a direct competitor does not mean they didn't do any research on the company or its market.
perhaps sales guy was going through 200 companies that day in a list sorted on website traffic rankings, or annual revenues, or hosting provider, or any number of other bits of info.
anyway, i run a startup, and i partially rely on received cold emails to get an understanding of the marketplace. we've found vendors, competitors, and VARs that we otherwise wouldn't have known existed. sorry, it's just the way it's done.