Think of marbles you may have played with as a child. The round beads are quite sturdy. The longer skinny beads and shapes which have points are more delicate. As with all jewelry its' best to treat it gently. The beads made in the US are made over mandrels which are coated to release the bead, but the holes are still quite large.
Many factors enter into price of an item.
One is the cost of labor in the country, another is the desirability and availability of an item. Beads made in Venice are handmade and few can be made in a day compared to the machine made beads of the Czech Republic. There are a limited number of people still working this ancient craft in Venice - so supply is also limited. And we feel, quite honestly, they are much more beautiful a result of the quality of the glass and the workmanship. As with all articles made by hand, the sizes and shapes will vary.