We use jabber in my office, and it's definitely higher friction than slack; this made me think of it as at least slightly a positive for the first time. We also have a wiki, and a searchable database for topical mailing lists, and those get used a lot.
If someone has to send me an IM to get an answer to something about our product, and I can't link the answer to them by just searching our wiki (or documentation if it's user-visible), then I file a note to add it.
I haven't ever felt the need to berate someone for asking me about easy to find information, because someone who isn't at least slightly embarrassed to have their question answered by a link to a resource they could have found on their own in under 30 seconds is probably going to have enough problems in other areas.
If someone has to send me an IM to get an answer to something about our product, and I can't link the answer to them by just searching our wiki (or documentation if it's user-visible), then I file a note to add it.
I haven't ever felt the need to berate someone for asking me about easy to find information, because someone who isn't at least slightly embarrassed to have their question answered by a link to a resource they could have found on their own in under 30 seconds is probably going to have enough problems in other areas.