Utility floating neutral, isolation transformers and getting a shock
First of all, just because the neutral is not bonded to ground at the pole does not mean that it isn't bonded to ground elsewhere, such as at the service entrance of a building.

Second, even if the secondary is completely floating with respect to ground, keep in mind that there's a significant amount of capacitance between the primary and secondary, and the primary is being driven with several thousand volts. This capacitive current can be quite significant. This is one reason that the secondary is grounded in the first place.