I am just curious...drainage is such a vital part of healthy plants, but why don't the majority of pots have holes?!
All the pots I use have drainage holes - if they don't have them when I buy the pot, I drill them - even if the pots are clay or ceramic pottery. It's extremely difficult to grow in a pot w/o drain holes if you're using it as the primary pot and not as a cache pot; and the margin for grower error is very small. One over-night rain or a simple over-application of water can easily do you in. Also, there is no way to flush the soil of accumulating salts, which will always loom on the horizon if you don't address it in some manner - like using deionized (distilled) water and being extremely careful about fertilizing. It's just not worth the risk, in my estimation.
I find the majority of pots HAVE holes actually. They are VERY necessary.
I use "antique" pots. I've had a lot of luck finding pottery from W. Germany. :) Yay flea markets & thrift shops! Since I can't bring myself to drill holes in something that old. I just use similar sized crappy plastic pots in them. Then pull out to water. My plants are happy, I'm happy & I have some really neat old stuff.
Any pretty pottery I purchase new without drainage gets hit with the drill. I learned the hard way to do this. Took one of my pretties out in a pot with no drainage. It rained, my plant drowned & the smell of plant death from overly moist soil is not pretty.
Drainage is best, but I do have a few plants in plastic pots "inside" pots without drain holes. This way I can leave them wet or drain the excess out and then replace them in their "pretty" pot. My house gets insanely hot in summer and my pepperomia seems to like being in that pot without the drain hole.