Back in his early days, when he was a young 24 year old, Lex thought that teleportation was the fastest and easiest way to get around. In many ways he was not wrong. However, teleporting via space laws had its own issues and constraints, not to mention that almost everyone anticipated it at higher levels which is why they were prepared for it.
Either he needed his skill in teleportation to be as great as everyone thought the Innkeepers was, and that would allow him to get past the regular limitations of teleportation, or he needed other ways of traveling. Thus, Lex found that in the situation where he had a strong enough karmic tie with whomever he was teleporting to, traveling via karmic lines was a good option.
