You have to be careful about weasel-wording when it comes to a number of vanity presses and their ilk.

"Your book will be available nationwide" - if people special order it or order it from their on-line stores.
"We'll be at (BEA, London Book Fair, Frankfurt Book Fair, etc.) - sure, they may be. Doesn't mean your books will be there or that they'll have a table there.
"We give the highest royalties in the business." - 80% net of 100 sales is not quite the same as 8% cover of 15000 sales. Do the math and see what works best for you given realistic numbers. Don't be fooled by gaudy percentages, especially if the publisher it talking "net". Find out how they derive net to begin with

The biggest take-away is don't get in a hurry to get published. Do your homework and you'll start recognizing weasel-wording soon enough.