As it would stand, the truth of the matter was that aliens had visited Earth before. Roswell was neither a hoax nor unique. It was simply a consequence of a world growing smaller as communication systems became more and more advanced, partly a result of said visitations. For the most part, past interactions between one of the planet Earth's more intelligent species of lifeform and the alien visitors were along the lines of obscure scientific surveys and tests disturbingly similar to attempts by some human scientists to estimate the intelligence of simians.
For any species capable of travelling the stars. Visiting planet Earth made about as much sense as backpacking through the Ural Mountains of Siberia with nothing but a flint and a compass. That is to say, most people would prefer to stay close to someplace within walking distance of a mall or a population density slightly higher than four sapient beings per parsec. Still, statistically speaking, there are bound to be some weirdos who find joy rides though a nowhere solar system fun. Just buzzing a frantic farmer or two and playing chicken with an F-16 for the heck of it. Maybe even bring home a bovine to show off to the guys at the office.