Titanium and high-end steel bikes are really a "lifestyle" choice, I'm guessing mostly attractive to older, traditional riders with a healthy budget and plenty of nostalgia.
More workhorse steel bikes are often the favoured weapon of choice for daily commuting, winter riding, touring etc.
Aluminium bikes are now the budget option for most uses, from full-on racing to daily pottering.
Carbon is both the competitive racer's choice and the choice of most reasonably affluent club riders and weekend warriors. A few of the older guys still ride steel/ti out of preference, but even most of the vets around here have discovered carbon or at least have both in their fleet.