Position isn't quantized; energy is.
An object having a position described by an irrational number does not store infinite information. The object isn't storing anything at all; it's just sitting at that location.
The person doing the decimal expansion has to store an infinite amount of information. What if the person just uses an infinite-series expression?
Another question - what if I just shift my reference frame to be one irrational unit offset from yours? Does the information encoded by object-positions in my reference frame now change?