Plan IO vs Reads in profiler
The row size numbers are estimates of the size of the data that actually moves between plan operators. Plan Explorer enhances this information by adding a calculated 'actual data size' value based on the actual number of rows multiplied by the estimated row size. These numbers can be useful for giving you feel for the size of data moving around.
The Profiler reads value reflects the number of pages read on behalf of the query to find the data that moves around the plan. In your case, the 17,268 reads are performed by the index seek on Table2.Index2. This is an inequality seek with a residual predicate:
This operation reads so many pages because it seeks to the position of the first record that meets the inequality Column3 <= ScalarString4, then tests the residual predicate ScalarString5. This row does not qualify, so the seek continues testing rows that meet the inequality and residual in key order until it finally finds a match for both conditions. The operator looks as if it seeks to produce a single row, but in reality it is hiding quite a lot of work. Note: The Table I/O tab is not a PRO-only feature, it is populated when you execute the query from PE directly (Get Actual Plan). The information is not collected in a regular query plan, so PE has no way to display it if you import a plan from SSMS.