The airlines, like most employers, look at everything. Past employment, schools, flying hours, background checks, community involvement, your attitude, your professionalism, it all matters. Now the big thing is certainly flying hours, but that does not mean that the other aspects are not important.You could have thousands of flying hours, but if the majors want to see a degree, you had better have one.
Past employment matters, but in the context of they want to see steady employment, not five different jobs in two years. Of course certain past jobs will stand out more than others.
Same thing with colleges. While a degree from Notre Dame would certainly look great, one from a state college will fit the bill just as well.