For myself, I test my dice. I do a few hundred rolls on each, with a program on my HP-41CX to speed up tracking results and crunching the data.
Even my old, worn D&D Basic Set dice are as random as can be measured. The ones that have a preference are visibly deformed. I have two old 20-siders that have bulged sides they don't like to stop on (not kept in the dice bag, of course) and a set of acrylic 6-siders with some sprue on one edge. Others like these have become perfectly random after the sprue was trimmed.
The only other lack of randomness I've run into was a 12 sider that was markedly denser on one side than the other (you could feel it in your palm, the bias showed within a few rolls) and some wooden 6-siders, also easily noticable both in hand and after a few rolls.
For all others, round edges or sharp, I've run several hundred dice through several hundred test rolls apiece over the years and not found anything sufficiently biased to show it in 250 rolls or more (much more, depending on how many sides it has.)
There is far more to what happens in the hand and on the table than to the shape of the dice's edges, IMO.
There is this, though. I used to do sleight of hand tricks with dice for fun. I'd roll numbers on command, or sequences, that sort of thing (with a wall bounce and the dice turning over on the table--not just sliding.) I used do sort of a Scarne trick routine with dice and cards.
It's a bit harder to control dice with sharp edges, especially on felt. They tend to grab at the corners and be a bit more unpredictable. Still, a good mechanic can make them do what they want. Part of the pit crew's job at a casino is to watch for mechanics. With the sharp edges, it's easier to see because it takes more care in the throw than round edged dice under the same circumstances.
So my guess is that that, and the impression the marks have that filled/printed pips and square edges makes the game more fair, drives what the casinos use.
Part of the reason dice are so widely used as randomizers is that even mediocre ones do a darn good job of being random when used fairly.
Speciality dice may be all they're cracked up to be, but to me it's like putting rollers on cam followers on an engine that runs well already. *shrug*