A couple of days ago, I received four emails from the same manufacturer's rep, containing a total of twenty-two images of new finish colors. Combined file size: Twenty-two meg.
This isn’t unusual. Almost daily, reps send us emails with huge attachments. I understand the desire to make the email attract attention, but only a little effort will accomplish that goal. A few carefully selected images should do the trick.
As for catalogues and other large documents, there is no reason to send them. A link to the file will suffice, assuming the files are online - and if they're not, why not?