No it doesn't matter. The tyre pressures in the handbook are just a bunch of random numbers made up my whoever can fit the most peanuts in their mouth.
If you think about it for a moment, That is probabally a lot closer to the truth than you might (At first thought) think!
What I mean about that is, that tyre presure is not, in normal day to day driving, a particularly precise requirement There is a
huge margin factored in anyway (To allow for varying load conditions, climate etc) and the actual running pressures day-to-day will be all over the place depending on the weather and the type of driving that you are doing. (Think
combined gas law!)
In the absence of any better data, 30 all round would be just fine for any normal car, with a bit more in the back if you are taking the whole family on holiday!
Obviously stupidly high pressures or flat would be bad, as would having significantly different pressures on each side of the same axle, but provided you avoid these obvious extremes the pressures you run at wont actually make that much difference!
Now, I am sure that in highly specialised and extreme environment such as F1 (where the difference between winning and losing is measured in milliseconds) that all these things are taken account of and that the pressures on the day will be calculated using data on air temp, track tarmac temperature even altitude (And other things besides no doubt)
But for any normal day to day driving the "OMGz My Tyres are out by 2psi" is nonsense!
