I’m an EE, and circuit 101 says current, like water, cannot flow unless there is a closed loop/path. In a battery, there must be a path between the + and the – terminals for the current to flow, i.e., the battery to drain. One can connect the battery + terminal to earth/concrete floor, but if there is no path back to the – terminal, no current will flow, and no drain will occur.
However, current drain is not the only way the battery gets weak. Since batteries generate electricity from chemical reaction internally, temperature has a big affect on the chemistry, i.e., low temperature slows down chemical reaction significiantly. I’m guessing that the concrete floor, being colder and a better heat conductor than a bench top, could have the effect of chilling the battery more. I don’t know if that would cause permanent damage or not, but maybe it depends on how cold it gets where you are, ’cause I guess you wouldn’t want a wet-cell battery to freeze.
Now, the funny thing is, for dry-cell disposable batteries (AA, C, D, etc.), they say to keep them in refrigerators to keep them fresh longer, i.e., slows down the internal chemical reaction. You just need to let them warm up enough before use.