At one point, paint and fuel were huge sources of exposure to lead. And it was not an issue, until it was. Lead being widely present in the environment due to pollution, it is difficult to evaluate the exposure level due to any specific source. This reduces the likelihood of further actions for sources of exposure that have lower average impact but may still have high impact for specific individuals.
Crystal glass is a known, legal way to add lead to your drinks, and studies have demonstrated that prolonged exposure to acidic liquids will provide you with quite a dose of lead. Strangely, manufactures of crystal items still seem to advertise on the basis that higher lead content means a more desirable product. Go figure.
That is what I thought, too. In the not-too-distant past, I tried to find information about this, but was not successful. I am no expert at locating that kind of information, though. All I found were anecdotal evidence of lead leaching from terra cotta items from Mexico, probably all referencing the same study to begin with.
About pottery, I found various mentions of the use of frits for glazes as something that made leaded glaze safer for workers using them at the manufacturing stage, but this has nothing to do with safety for the end-user.