It may be the case that developer offerings are easier to sell into bigcos than other services. For my part, I have (a) had no luck selling products into enterprises using passive sales techniques (blogging "developer evangelist"-type strategies being an example of passive sales), and (b) talked to a bunch of other people who report similar results.

Regarding consulting: yes, 3 full-time consultants as staff aug is hard to sell. But most consulting projects aren't like that. Our typical project is 2 people, 2 weeks; we scale down to 1 person/week easily. A 1 p/w project isn't hard to sell at all.