I don't actually use a random encounter table. It's not that I despise them or anything, I just tend to usually have at least ten or as many as twenty "random" encounters roughed out for any particular campaign. The reason I don't set them up as a table though, is so that I can use the encounter that is best suited for the situation the party is in. This way I don't have to come up with a plausible reason why some creature(s) that are normally found in a temperate wood setting, just so happens to found in the middle of the largest city in the area. Or worse, the party is making their way over a rocky surface and try to justify how the party is being confronted by a shambling mound, when there has been no vegetation for the past 10 miles.
Now I know that if you are using a premade campaign, there is usually a random encounter table or so included with it. Just because it is there, doesn't mean that you can't utilize it in a slightly different manor.
The other reason that I don't really use a set table is that if I use say 5 of the encounters from a group of 20 on a particular game session, then I make sure to replace them with a new encounter by the next session. This way the players don't grow bored with having to fight the same creature(s) for the duration of the campaign.
One thing that I have noticed about almost all of the premade encounter tables is that they seem to usually be all combat type encounters. I like to include situations that don't call for any combat. Maybe there is a local patrol passing by and just want to obtain some information, or a local family may have had a wheel break on a wagon and need help, or even a merchant that is willing to sell some items to the party or maybe purchase some extra stuff that they need to dispose of.
I guess that I would characterize myself as tayloring them to better fitting my game. I will admit that I do sometimes roll a die or so before giving the party the initial information of an encounter. Keeps them woundering if the outcome would have been different depending on what number came up.